高速气体与椭圆柱云相互作用的数值研究

高速颗粒流在天文、自然灾害、工业安全、医疗工业和国防等领域有着重要应用。采用基于分层流模型的直接数值模拟方法,对平面激波与椭圆柱云的相互作用进行数值研究,重点关注椭圆柱横截面的不同长短轴之比和椭圆柱横截面长轴与来流方向所成角度对流场的影响,从气体来流方向上的速度、x轴和y轴方向上的均方根速度、动能、内能和湍动能的分布上进行分析,对能量在计算域的上游区域、椭圆柱云区域和下游区域进行定量分析。同时针对椭圆柱改进了一维体积平均模型,利用该模型拟合了由直接数值模拟得到的反射激波和透射激波位置,获得了最适配的一维体积平均模型中的人工有效阻力系数,并探讨此系数的分布规律。

Numerical Study of the Interaction between High-Speed Gas and Elliptical Column Cloud

High-speed particle-laden flow has important applications in astronomy,natural disasters,industrial safety,medical industry,and national defense.In this work,a direct numerical simulation method based on the stratified flow model is used to study the interaction between a planar shock wave and an elliptical column cloud.The influence of the aspect ratio and the tilt angle,the distributions of the flow velocity,RMS velocities along x axis,kinetic energy,internal energy,and turbulent kinetic energy are analyzed;energy values in the upstream region,the elliptical column cloud region and the downstream region of the computational domain are quantitatively analyzed.The 1-D volume-average model is improved for elliptical columns.Based on this model,the appropriate artificial effective drag coefficients are decided by fitting the positions of the reflected shock and the transmitted shock from the direct numerical simulation results,and the distribution of the optimal artificial effective drag coefficients is also discussed.